School is an institution built on the axiom that learning is the result of teaching. And institutional wisdom continues to accept this axiom, despite overwhelming evidence to the contrary.
Most learning happens casually, and even most intentional learning is not the result of programmed instruction. Normal children learn their first language casually, although faster if their parents pay attention to them. Most people who learn a second language well do so as a result of odd circumstances and not of sequential teaching. They go to live with their grandparents, they travel, or they fall in love with a foreigner. Fluency in reading is also more often than not a result of such extra-curricular activities. Most people read widely, and with pleasure out of school.
Everyone learns how to live outside school. We learn to speak, to think, to love, to feel, to play, to curse, to politick and to work without interference from a teacher. Even children who are under a teacher's care day and night are no exception to the rule. Orphans, idiots and schoolteachers' sons learn most of what they learn outside the "educational" process planned for them. Teachers have made a poor showing in their attempt at increasing learning among the poor. Poor parents who want their children to go to school are less concerned about what they will learn than about the certificate and money they will earn. And middle-class parents entrust their children to a teacher's care to keep them from learning what the poor learn on the streets. Increasingly, educational research demonstrates that children learn most of what teachers pretend to teach them from peer groups, from comics, from chance observations, and above all from mere participation in the ritual of school.